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Updated: May 26, 2026
13:44
Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
Wave energy extraction by coupled resonant absorbers.
Summary
A new resonant over-topping absorber (ROTA) wave energy converter (WEC) enhances efficiency by coupling internal water sloshing resonances with device resonance. This innovative design broadens the optimal operating frequency range for wave power absorption.
Area of Science:
- Marine Engineering
- Renewable Energy Systems
- Hydrodynamics
Background:
- Classical wave energy converters (WECs) often have limited operational efficiency tied to specific frequencies.
- Resonance is crucial for maximizing power absorption in single-degree-of-freedom WECs.
- Improving power take-off characteristics requires extending the efficient frequency range.
Purpose of the Study:
- Introduce a novel wave energy converter (WEC) concept: the resonant over-topping absorber (ROTA).
- Demonstrate methods to enhance WEC efficiency by introducing multiple resonances.
- Investigate the exploitation of coupled resonance for improved wave power absorption.
Main Methods:
- Review classical WEC theories and resonance principles.
- Develop a coupled resonant absorber concept by integrating a water tank into a WEC.
- Analyze the hydrodynamic characteristics of a submerged buoyant circular cylinder tethered to the seafloor.
Main Results:
- A coupled resonant effect can be achieved by incorporating an internal water tank within a WEC.
- The ROTA device exploits the coupling between water sloshing frequencies and the cylinder's natural resonance.
- This coupling allows for rotary motion and potentially broader frequency efficiency.
Conclusions:
- The ROTA device presents a novel approach to wave energy conversion.
- Coupled resonance significantly enhances power take-off characteristics by broadening the efficient operating frequency range.
- The ROTA concept offers a promising advancement in renewable wave energy technology.
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